FIELD OF THE INVENTION
[0001] The present disclosure relates generally to the field of orthopedic implants, and
more particularly relates to orthopedic external fixation devices.
BACKGROUND
[0002] External fixation devices have been successfully used in orthopedics for a long time.
Hexapod systems in particular have proven to be valuable clinical tools for treating
a variety of conditions. One well known hexapod system is the Taylor Spatial Frame
(TSF) by Smith and Nephew. The TSF has demonstrated clinical success for decades and
has inspired development of many similar systems.
[0003] In general, orthopedic hexapods may include first and second bases, which may generally
be in the form of rings, fixation components, and up to six variable length struts.
The fixation components are connected to each of the bases to secure the bases to
the patient's bone fragments. The six struts connect the two bases to one another
and allow for precise manipulation of the bases, and hence the patient's bone fragments,
in six degrees of freedom.
[0004] Generally speaking, in the most basic sense, the variable length struts include a
strut body, a threaded rod, and a mechanism for adjustment. In use, the threaded rod
may translate relative to the strut body to change the overall length of the strut.
Thus arranged, by individually adjusting each of the struts, manipulation of the relative
positions of the first and second bases, and hence the patient's bone fragments coupled
thereto is possible. Patients or caregivers adjust the strut lengths according to
a computer-generated prescription to achieve a desired correction.
[0005] Medical device companies have been developing external fixation struts with additional
telescopic bodies, various acute and precise adjustment mechanisms, and assorted joint
designs.
[0006] It is with respect to these and other considerations that the present improvements
may be useful.
WO2014159824A2 relates to an external bone fixation device.
SUMMARY
[0007] This Summary is provided to introduce a selection of concepts in a simplified form
that are further described below in the Detailed Description. This Summary is not
intended to identify key features or essential features of the claimed subject matter,
nor is it intended as an aid in determining the scope of the claimed subject matter.
[0008] An external fixation strut is disclosed. In one example of an embodiment, the external
fixation strut comprises a strut body operatively associated with a first connector,
a threaded rod including threads formed thereon, the threaded rod being operatively
associated with a second connector, and an acute adjustment mechanism selectively
disengageable from the threads of the threaded rod. In use, the threaded rod is rotationally
fixed relative to the strut body so that movement of the threaded rod relative to
the strut body moves the first connector relative to the second connector. The acute
adjustment mechanism comprises an actuator body, a mobile jaw that is engageable with
the threads of the threaded rod, and a disengagement member configured to interact
with the mobile jaw to disengage the mobile jaw from the threads of the threaded rod.
In use, the disengagement member is selectively movable from a first position to a
second position such that when in the second position, the disengagement member interacts
with the mobile jaw to disengage the mobile jaw from the threads of the threaded rod
to enable the first and second connectors to be adjusted acutely.
[0009] In some embodiments, the mobile jaw includes a threaded surface configured to engage
with the threads of the threaded rod.
[0010] In some embodiments, the acute adjustment mechanism includes two substantially oppositely
positioned mobile jaws configured to engage with threads of the threaded rod on substantially
opposite sides of the threaded rod.
[0011] In some embodiments, the substantially oppositely positioned mobile jaws each include
a threaded surface configured to engage with threads of the threaded rod.
[0012] In some embodiments, the mobile jaw is biased to engage with the threaded rod.
[0013] In some embodiments, the mobile jaw is biased to disengage from the threaded rod.
[0014] In some embodiments, the disengagement member is a button configured to interact
with the mobile jaw to disengage the mobile jaw from the threads of the threaded rod
when the button is moved by a user from the first position to the second position.
[0015] In some embodiments, the button includes an angled face configured to interact with
one or more faces of the mobile jaw to disengage the mobile jaw from the threads of
the threaded rod.
[0016] In some embodiments, the disengagement member is configured to translate toward the
mobile jaw when moved from the first position to the second position to disengage
the mobile jaw from the threaded rod and the disengagement member is configured to
rotate about the disengagement member's axis of translation to lock the acute adjustment
mechanism in a state of free movement where the mobile jaw is disengaged from the
threaded rod.
[0017] In some embodiments, the disengagement member is configured to translate away from
the mobile jaw when moved from the first position to the second position to enable
the mobile jaw to disengage from the threaded rod.
[0018] In some embodiments, the disengagement member includes a containment device configured
to prevent the mobile jaw from moving away from the threads of the threaded rod when
the containment device is coupled to the acute adjustment mechanism.
[0019] In some embodiments, the containment device is arranged and configured as an ID band
for identifying each respective strut.
[0020] In some embodiments, the mobile jaw is configured to translate away from the threaded
rod when interacted with by the disengagement member.
[0021] In some embodiments, the mobile jaw is configured to pivot away from the threaded
rod when interacted with by the disengagement member.
[0022] In some embodiments, the actuator body includes a threaded collar that couples the
actuator body with the strut body.
[0023] In some embodiments, the actuator body includes channels configured to guide the
movement of the mobile jaw when the mobile jaw is interacted with by the disengagement
member.
[0024] In some embodiments, the actuator body includes channels configured to constrain
the movement of protrusions on the mobile jaw when the mobile jaw is interacted on
by the disengagement member.
[0025] In some embodiments, the mobile jaw has one or more angled faces configured to interact
with the disengagement member to move the mobile jaw away from the threaded rod.
[0026] In some embodiments, the external fixation strut further comprises a rotatable sleeve
that is sized to fit over the outside of the actuator body with one or more openings
for access to the disengagement member.
[0027] In some embodiments, when the rotatable sleeve is rotated relative to the actuator
body, access to the disengagement member is blocked.
[0028] In some embodiments, when the rotatable sleeve is rotated relative to the actuator
body a portion of opening interacts with the disengagement member to disengage the
mobile jaw from the threaded rod.
[0029] In some embodiments, the external fixation strut further comprises a precise adjustment
mechanism comprising a lock positioned between the strut body and the actuator body;
wherein the lock is movable between a first position and a second position, in the
first position, the lock is arranged and configured to rotationally fix the strut
body relative to the actuator body in the second position, the lock is arranged and
configured to enable rotation of the actuator body relative to the strut body to move
the threaded rod longitudinally relative to the strut body.
[0030] In some embodiments, the lock of the precise adjustment mechanism includes a base
coupled to the strut body, a plunger biased away from the base, and a cavity formed
in the actuator body, the cavity arranged and configured to receive the plunger to
restrict rotational movement of the strut body relative to the actuator body.
[0031] In some embodiments, the lock of the precise adjustment mechanism includes a pivot
coupled to the actuator body, the pivot being biased toward the strut body and being
arranged and configured to fit in a notch formed in the strut body to restrict rotational
movement of the strut body relative to the actuator body when a portion of the pivot
is positioned in the notch in the strut body.
[0032] In some embodiments, the actuator body includes openings for receiving projections
of a band to prevent disengagement of the mobile jaw from the threaded rod.
[0033] In some embodiments, the external fixation strut further comprises a band, wherein
the band is arranged and configured to cover the disengagement member when the band
is positioned on the acute adjustment mechanism to prevent access to the disengagement
member.
[0034] In some embodiments, the first and second connectors are first and second U-joints,
respectively, the first and second U-joints including first and second clevises, a
central body having a plurality of threaded openings, and a plurality of set screws
arranged and configured to couple the central body to the first and second joint clevises.
[0035] In some embodiments, the external fixation strut further comprises a tracer pin operatively
coupled to the threaded rod and a locking sleeve operatively coupled to the strut
body, the locking sleeve including an opening arranged and configured to receive the
tracer pin, the locking sleeve being arranged and configured to prevent movement of
the track pin and thus to prevent adjustment of the external fixation strut.
[0036] An alternate embodiment of an external fixation strut may include a strut body, a
threaded rod substantially rotationally fixed relative to the strut body, an acute
adjustment mechanism, and an optional precise adjustment mechanism comprising a lock
between the strut body and the actuator body. The acute adjustment mechanism may be
selectively disengageable from threads of the threaded rod and include an actuator
body, a mobile jaw that is engageable with the threads of the threaded rod, and a
disengagement member configured to interact with the mobile jaw to disengage the mobile
jaw from the threads of the threaded rod. The lock may be biased to fix the strut
body with the actuator body rotationally, but may be activated to allow for rotation
of the actuator body relative to the strut body to move the threaded rod longitudinally
relative to the strut body.
[0037] Another embodiment of an external fixation system may include an upper base, a lower
base, and at least two struts coupled between the upper base and the lower base. At
least one of the struts includes a strut body, a threaded rod substantially rotationally
fixed relative to the strut body, and an acute adjustment mechanism selectively disengageable
from the threads of the threaded rod. The acute adjustment mechanism may include an
actuator body, a mobile jaw that is engageable with the threads of the threaded rod,
and a disengagement member configured to interact with the mobile jaw to disengage
the mobile jaw from the threads of the threaded rod. At least one of the struts may
optionally include a precise adjustment mechanism comprising a lock between the strut
body and the actuator body. The lock may be biased to fix the strut body with the
actuator body rotationally, but may be activated to allow for rotation of the actuator
body relative to the strut body to move the threaded rod longitudinally relative to
the strut body.
[0038] Still another embodiment, outside the scope of the claims, is directed to a method
of adjusting an external fixation strut. The method may include disengaging an acute
adjustment mechanism of the external fixation strut from threads of a threaded rod
of the external fixation strut, wherein the acute adjustment mechanism is biased toward
an engaged state, and wherein the threaded rod is substantially rotationally fixed
relative to a strut body of the external fixation strut, and moving the acute adjustment
mechanism relative to the threaded rod to a position closer to a final adjustment
position. The method may also include engaging the acute adjustment mechanism of the
external fixation strut to the threads of the threaded rod by removing force against
the bias toward an engaged state, releasing a lock of a precise adjustment mechanism
that is configured to lock between the strut body and the acute adjustment mechanism,
and with the lock of the precise adjustment mechanism in a released state, rotating
the acute adjustment mechanism relative to the strut body to move the threaded rod
longitudinally relative to the strut body.
[0039] Yet another embodiment, outside the scope of the claims, is directed to a method
of adjusting an external fixation strut. The method may include disengaging an acute
adjustment mechanism of the external fixation strut from threads of a threaded rod
of the external fixation strut, wherein the acute adjustment mechanism is biased toward
a disengaged state, and wherein the threaded rod is substantially rotationally fixed
relative to a strut body of the external fixation strut. The method may include moving
the acute adjustment mechanism relative to the threaded rod to a position closer to
a final adjustment position, engaging the acute adjustment mechanism of the external
fixation strut to the threads of the threaded rod by applying force against the bias
toward a disengaged state, and releasing a lock of a precise adjustment mechanism
that is configured to lock between the strut body and the acute adjustment mechanism.
With the lock of the precise adjustment mechanism in a released state, the acute adjustment
mechanism may be rotated relative to the strut body to move the threaded rod longitudinally
relative to the strut body.
[0040] Embodiments of the present disclosure provide numerous advantages. By incorporating
an acute adjustment mechanism including one or more mobile jaws and a disengagement
member, the external fixation strut facilitates gross adjustment of the length of
the strut for acute adjustment and simplified installation and removal. In addition,
the embodiments disclosed within the present disclosure describe a new strut design
which focuses on safety with features impeding accidental adjustment of the acute
and precise adjustment mechanisms. The embodiment of the present disclosure also focus
on efficiency with components configured to preserve the maximum amount of working
length on the threaded rod.
[0041] Further features and advantages of at least some of the embodiments of the present
invention, as well as the structure and operation of various embodiments of the present
invention, are described in detail below with reference to the accompanying drawings
BRIEF DESCRIPTION OF THE DRAWINGS
[0042]
FIG. 1A illustrates a perspective view of an example of an embodiment of an external
fixation strut in accordance with principles of the present disclosure.
FIG. 1B illustrates a back elevation view of the external fixation strut shown in
FIG. 1A.
FIG. 1C illustrates a front elevation view of the external fixation strut shown in
FIG. 1A.
FIG. 2 illustrates an exploded, perspective view of the external fixation strut shown
in FIG. 1A.
FIG. 3A illustrates a detailed, front elevation view of an example of an embodiment
of an acute adjustment mechanism that can be used in combination with the external
fixation strut shown in FIG. 1A.
FIG. 3B illustrates a detailed, back elevation view of the acute adjustment mechanism
shown in FIG. 3A.
FIG. 3C illustrates a front elevation view of the acute adjustment mechanism shown
in FIG. 3A, the acute adjustment mechanism shown with a band removed to illustrate
a rotating sleeve.
FIG. 3D illustrates a front elevation view of the acute adjustment mechanism shown
in FIG. 3C with the rotating sleeve rotated counterclockwise.
FIG. 3E illustrates a cross-sectional view of the acute adjustment mechanism shown
in FIG. 3C, the acute adjustment mechanism including threads engaged with a threaded
rod.
FIG. 3F illustrates a cross-sectional view of the acute adjustment mechanism shown
in FIG. 3D, the acute adjustment mechanism shown with its threads disengaged from
the threaded rod.
FIG. 4 illustrates an exploded, perspective view of an example of an embodiment of
a band for use with the external fixation strut shown in FIG. 1A.
FIG. 5A illustrates an exploded, perspective view of an example of an embodiment of
the acute adjustment mechanism that may be used in combination with the external fixation
strut shown in FIG. 1A.
FIG. 5B illustrates an alternate, exploded, perspective view of the acute adjustment
mechanism shown in FIG. 5A.
FIG. 6A illustrates a side elevation view of an example of an embodiment of a precise
adjustment mechanism that may be used in combination with the external fixation strut
shown in FIG. 1A, the precise adjustment mechanism including a plunger positioned
in a locked position.
FIG. 6B illustrates a side elevation view of the precise adjustment mechanism shown
in FIG. 6A, the precise adjustment mechanism including the plunger positioned in an
unlocked position.
FIG. 6C illustrates an exploded, perspective view of the precise adjustment mechanism
shown in FIG. 6A and a portion of the acute adjustment mechanism shown in FIG. 5B.
FIG. 7A illustrates a perspective view of an example of an embodiment of a universal
joint that may be used in combination with an external fixation strut.
FIG. 7B illustrates an exploded, perspective view of the universal joint shown in
FIG. 7A.
FIG. 8A illustrates a top plane view of an example of an embodiment of an angled button
that may be in combination with the external fixation strut shown in FIG. 1A.
FIG. 8B illustrates a top plane view of an example of an embodiment of a rounded button
that may be in combination with the external fixation strut shown in FIG. 1A.
FIGS. 9A and 9B illustrate an example of an embodiment of an external fixation strut
with the rounded button of FIG. 8B, the rounded button illustrated in a non-activated
or non-pushed position, and consequently the acute adjustment mechanism is engaged
with the threaded rod.
FIGS. 9C and 9D illustrate an example of an embodiment of an external fixation strut
with the rounded button of FIG. 8B, the rounded button illustrated in an activated
or pushed position, and consequently, the acute adjustment mechanism is disengage
with the threaded rod, and additionally the rotating sleeve has been rotated.
FIG. 10 illustrates a perspective view of an example of an embodiment of a locking
sleeve coupled to the external fixation strut shown in FIG. 1A.
FIG. 11A illustrates a perspective view of an alternate example of an external fixation
strut in accordance with principles of the present disclosure.
FIG. 11B illustrates a back elevation view of the external fixation strut shown in
FIG. 11A.
FIG. 11C illustrates a front elevation view of the external fixation strut shown in
FIG. 11A.
FIG. 12 illustrates an exploded, perspective view of the external fixation strut shown
in FIG. 11A.
FIG. 13A illustrates a side elevation view of an example of an embodiment of an acute
adjustment mechanism that can be used in combination with the external fixation strut
shown in FIG. 11A.
FIG. 13B illustrates a side elevation view of the acute adjustment mechanism shown
in FIG. 13A with a band removed.
FIG. 13C illustrate an opposite side elevation view of the acute adjustment mechanism
shown in FIG. 13B with a button pushed.
FIG. 13D is a cross-sectional view of the acute adjustment mechanism shown in FIG.
13B.
FIG. 13E is a cross-sectional view of the acute adjustment mechanism shown in FIG.
13C.
FIG. 14A is a side elevation view of the acute adjustment mechanism shown in FIG.
13E with the button rotated counterclockwise, as well as pushed.
FIG. 14B is a perspective view of the acute adjustment mechanism shown in FIG. 14A
with the actuator body of the device removed to view internal components of the mechanism.
FIG. 15A is a perspective view of the acute adjustment mechanism shown in FIG. 14A
showing a portion of an example of an embodiment of a precise adjustment mechanism.
FIG. 15B is a perspective view of the acute adjustment mechanism shown in FIG. 15A
with the band removed.
FIG. 15C is a perspective view of the acute adjustment mechanism shown in FIG. 15B
with the actuator body of the device removed to view internal components of the mechanism.
FIG. 15D is a perspective view of the acute adjustment mechanism shown in FIG. 15B
with the precise adjustment mechanism in an unlocked position.
FIG. 15E is a perspective view of the acute adjustment mechanism shown in FIG. 15D
with the actuator body of the device removed to view internal components of the mechanism.
FIG. 16 is a perspective view of an interior portion of the acute adjustment mechanism
shown in FIG. 15A.
FIG. 17 is a perspective view of an alternate example of an embodiment of an external
fixation strut in accordance with principles of the present disclosure.
FIG. 18A is a top, perspective view of the external fixation strut shown in FIG. 17,
the view illustrating an example of an embodiment of an acute adjustment mechanism
and band.
FIG. 18B is a perspective view of the acute adjustment mechanism shown in FIG. 18A
with the actuator body of the device removed to view internal components of the mechanism.
FIG. 18C is a perspective view of the acute adjustment mechanism shown in FIG. 18A
with the band removed.
FIG. 18D is a perspective view of the acute adjustment mechanism shown in FIG. 18C
with a portion of the device removed to view internal components of the mechanism.
FIG. 19 is a perspective view of an alternate example of an embodiment of an external
fixation strut in accordance with principles of the present disclosure.
FIG. 20A is a top, perspective view of the external fixation strut shown in FIG. 19,
the view illustrating an example of an embodiment of an acute adjustment mechanism
and band.
FIG. 20B is a perspective view of the acute adjustment mechanism shown in FIG. 20A
with the band removed.
FIG. 20C is a perspective view of the band shown in FIGS. 20A and 20B.
FIG. 20D is a perspective view of the acute adjustment mechanism shown in FIGS. 20A
and 20B with the actuator body of the device removed to view internal components of
the mechanism.
FIG. 20E is a perspective view of the acute adjustment mechanism shown in FIGS. 20A
and 20B with a portion of the device removed to view internal components of the mechanism.
FIG. 20F is a top, perspective view of the external fixation strut shown in FIG. 19,
the view illustrating the acute adjustment mechanism and showing the disengagement
member in an activated position.
FIG. 20G is a perspective view of the acute adjustment mechanism shown in FIG. 20F
with the actuator body of the device removed to view internal components of the mechanism.
FIG. 21A is a perspective view of most components of the acute adjustment mechanism
shown in FIG. 20F with a temporary or acute band installed to hold the disengagement
member in an activated position.
FIG. 21B is a perspective view of the temporary or acute shown in FIG. 21A.
FIG. 22A is a perspective view of an alternate example of an embodiment of a temporary
or acute band that may be used with the eternal fixation strut;
FIG. 22B is a top view of the temporary or acute band shown in FIG. 22A.
FIG. 22C is a bottom view of the temporary or acute band shown in FIG. 22A.
FIG. 22D is a side view of the temporary or acute band shown in FIG. 22A.
DETAILED DESCRIPTION
[0043] For the purposes of promoting an understanding of the principles of the present disclosure,
reference will now be made to the embodiments illustrated in the figures and specific
language will be used to describe the same. The external fixation struts of the present
disclosure may, however, be embodied in many different forms and should not be construed
as being limited to the embodiments set forth herein. Rather, these embodiments are
provided so that this disclosure will convey certain aspects of the external fixation
struts to those skilled in the art. As such, it will be understood that no limitation
of the scope of the present disclosure is hereby intended. Any alterations and further
modifications in the described embodiments, and any further applications of the principles
of the present disclosure as described herein are contemplated as would normally occur
to one skilled in the art to which the disclosure relates. In the drawings, like numbers
refer to like elements throughout unless otherwise noted.
[0044] Referring to FIGS. 1A-10, in one example of an embodiment, an external fixation strut
100 is disclosed. As shown in the example embodiment, the external fixation strut
100 may include a strut body 110, a threaded rod 120 substantially rotationally fixed
relative to the strut body 110 so that movement of the threaded rod 120 axially translates
or moves the threaded rod 120 relative to the strut body 110 (e.g., movement of the
threaded rod 120 is limited to translation relative to the strut body 110), an acute
adjustment mechanism 200 selectively disengageable from threads of the threaded rod
120, and a precise adjustment mechanism 300.
[0045] In one example of an embodiment, the acute adjustment mechanism 200 includes an actuator
body 210 that includes a threaded collar 250, a spring-loaded mobile jaw 220 including
associated biasing springs 214, and one or more disengagement members 230 that are
configured to interact with the mobile jaw 220. As shown, the actuator body 210 may
include apertures 216 to receive at least a portion of the disengagement members 230.
The disengagement members 230 may be in the form of one or more buttons, but other
embodiments are envisioned including, for example, one or more wedges, screws, cams,
or any other mechanism now known or hereafter developed.
[0046] In the illustrated embodiment, the external fixation strut 100 may also include a
rotating sleeve 240. In use, the rotating sleeve 240 is arranged and configured to
fit over the outside of the actuator body 210. The rotating sleeve 240 may include
openings 260 to provide access to the disengagement members 230 for reasons that will
be described in greater detail below.
[0047] The threaded collar 250 is arranged and configured to couple the actuator body 210
to the strut body 110. In one example of an embodiment, the actuator body 210 may
include one or more channels 212 (FIG. 5B) to guide the path of the mobile jaws 220
and the associated springs 214. In use, the associated springs 214 bias the mobile
jaws 220 against the threaded rod 120 and toward the disengagement members 230. For
example, the mobile jaws 220 have faces 222 that interact with surfaces 232 of the
disengagement members 230 so that when the disengagement members 230 are pressed inward,
the mobile jaws 220 move (e.g., separate and disengage) from the threaded rod 120
so that the strut length of the external fixation strut 100 can be adjusted acutely.
In use, the acute adjustment mechanism 200 facilitates gross adjustment. For example,
when installing an external fixation system, a surgeon may initially implant the external
fixation system with the acute adjustment mechanism 200 disengaged from the threaded
rod 120 (e.g., the mobile jaws 220 may be disengaged from the threaded rod 120). Thus
arranged, the surgeon can correct the patient's deformity acutely (making gross corrections
in the operating room). Once the surgeon has completed placing, positioning, implanting,
etc. the external fixation system, the acute adjustment mechanism 200 may be moved
to the activated, coupled, etc. position so that the acute adjustment mechanism 200
engages the threaded rod 120 (e.g., mobile jaws 220 engage the threaded rod 120) to
lock, fix, etc. the position of the external fixation struts. Thereafter, the struts
can be adjusted in small increments using the precise adjustment mechanism 300, for
example, by the patient in connection with daily adjustments needed to comply with
the prescription.
[0048] In one example of an embodiment, as shown, the precise adjustment mechanism 300 includes
a body 310, a plunger 320, and a spring 330. The spring 330 biases the plunger 320
to an extended position beyond an outer edge 312 of the body 310 and into a cavity
252 of the threaded collar 250. The body 310 cannot turn as long as a portion of the
plunger 320 is in the cavity 252 of the threaded collar 250.
[0049] In one example of an embodiment, as shown, the external fixation strut 100 may also
include bands 400, as will be described herein. In addition, and/or alternatively,
the external fixation strut 100 may also include and one or more connectors 500 to
couple the external fixation strut 100 to one or more bases, as will be described
in greater detail below. In use, the connectors 500 may be in the form of a Universal
joint (U-joint) as shown, alternatively however any other now known or hereafter developed
connector can be used such as, for example, ball joints, threaded ends, etc.
[0050] Referring to FIGS. 3A-3F and 5A-5B, the acute adjustment mechanism 200 will be described
in greater detail. The channels 212 formed in the actuator body 210 that guide the
path of the mobile jaws 220 and their springs 214 are illustrated in FIGS. 3E, 3F,
and 5B. In the illustrated embodiment, the acute adjustment mechanism 200 includes
first and second mobile jaws 220. In use, the first and second mobile jaws 220 are
biased to couple with the threads of the threaded rod 120 by the springs 214. The
mobile jaws 220 shown include threaded portions that interact with the threaded rod
120, but in other embodiments, mobile jaws may include other structure for interacting
with the threaded rod including, for example, knurling, a softer material, or any
other structure or material that is capable of interacting with the threads of the
threaded rod 120. In use, the mobile jaws 220 may also be arranged and configured
to interact with the disengagement members 230. For example, the mobile jaws 220 may
include faces 222 that interact with surfaces 232 of the disengagement members 230.
Apertures 216 (FIGS. 5A and 5B) formed in the sides of the actuator body 210 may constrain
the two opposing disengagement members 230. In use, the disengagement members 230
are designed so that they can be pressed from outside of the actuator body 210 toward
the threaded rod 120 so that when the disengagement members 230 are pressed inward,
the mobile jaws 220 disengage from the threaded rod 120 enabling the strut length
of the external fixation struts 100 to be adjusted acutely. For example, in one embodiment,
the geometry of the disengagement members 230 inside of the actuator body 210 may
be shaped like a wedge, although other suitable configurations are envisioned. The
faces 232 of this wedge interact with the faces 222 of the mobile jaws 220 so that
when the disengagement members 230 are pressed inward, the mobile jaws 220 move (e.g.,
separate and disengage) from the threaded rod 120 (FIG. 3F) enabling the threads formed
on the mobile jaws 220 to be disengaged from the threads formed on the threaded rod
120 and thus enable the strut length to be adjusted acutely.
[0051] The mobile jaws 220 may be constrained within the actuator body 210 by the channel
212 formed in the actuator body 210 (FIGS. 3E, 3F, and 5B) so that translation toward
and away from the threaded rod 120 is accomplished without any rotation. As previously
mentioned, the external fixation strut 100 may also include a rotating sleeve 240
that fits over the outside of the actuator body 210 with openings 260 for providing
access to the disengagement members 230. In use, rotating the sleeve 240 depresses
the disengagement members 230 and locks the disengagement members 230 in the depressed
position. Thus arranged, the rotating sleeve 240 allows for multiple struts to be
adjusted acutely at once because the user is not required to keep the disengagement
members 230 depressed by hand.
[0052] As previously mentioned, the external fixation strut 100 may also include a threaded
collar 250. In use, the threaded collar 250 connects the actuator body 210 to the
strut body 110. The threaded collar 250 may be slid up the base of the strut body
110 and threaded into the base of the actuator body 210. As shown, the acute adjustment
mechanism 200 may also include a first washer 280 and a second washer 282 (FIG. 2).
Washers 280, 282 may be positioned between the threaded collar 250 and the strut body
110, and between the strut body 110 and the actuator body 210. The washers 280, 282
act as spacers and reduce friction. The washer 282 between the strut body 110 and
the actuator body 210 may also further constrain the mobile jaws 220 and disengagement
members 230. The mobile jaws 220 may be constrained within the acute adjustment mechanism
200 by the channels 212. The channels 212 inside the actuator body 210 may correspond
to (substantially match) a rectangular protrusion 224 (FIGS. 5A and 5B) on the top
of the mobile jaws 220. In use, this constrains the mobile jaws 220 to translation
toward and away from the threaded rod 120 and prevents the mobile jaws 220 from rotating
out of position. Alternatively, the mobile jaws of some embodiments may have posts
on the jaws that align with holes on the actuator body and the rotating sleeve.
[0053] Referring to FIG. 4, as previously mentioned, the external fixation strut 100 may
also include a band 400. In some embodiments, the bands 400 may be arranged and configured
as an identification (ID) band for identifying each particular strut in the external
fixation system. As such, the bands 400 may be provided to numerically identify strut
assemblies so that each strut assembly may be distinguished for a prescription. In
use, the bands 400 are coupled to the external fixation struts 100. For example, as
shown, in one example of an embodiment, the band 400 may be slid down over the top
of the actuator body 210 by the action arrows in FIG. 4. Pegs , projections, etc.
410 on the band 400 are sized and configured to be received by holes 218 formed in
the actuator body 210. In use, the pegs, projections, etc. 410 prevent the mobile
jaws 220 from disengaging from the threaded rod 120 when the band 400 is coupled to
the actuator body 210. In the illustrated embodiment, the band 400 has a body 420
which covers the disengagement members 230 so that the buttons are not accessible
when the band 400 is positioned over the actuator body 210. In some embodiments, the
body 420 may include a space, a slot, a channel, or the like 430 to receive a tab,
a projection, or the like 242 (FIGS. 5A and 5B) of the rotating sleeve 240.
[0054] The band 400 provides a safety feature and reduces the risk of inadvertent acute
adjustment of the strut assembly by inhibiting access to the disengagement members
230 (e.g., inhibits accidental pressing of the buttons). Holes, pegs, and geometric
features on the band, actuator body, and rotating sleeve may also or alternatively
be used to provide easy placement of the band in the proper orientation. Acute adjustment
generally takes place clinically during application of the external fixation frame
or during strut change-outs. The bands 400 may be helpful to avoid inadvertent acute
adjustment when a patient is adjusting struts using precise adjustment mechanisms
to comply with an adjustment prescription such as, for example, when adjusting the
struts at home utilizing a precise adjustment mechanism to comply with the prescription.
[0055] Referring to FIGS. 6A-6C, the precise adjustment mechanism 300 will be described
in greater detail. As will be described in greater detail, the precise adjustment
mechanism 300 enables the strut length of the external fixation struts 100 to be adjusted.
For example, as previously mentioned, the precise adjustment mechanism 300 may be
used by patients during daily adjustments. As shown, in one example of an embodiment,
the precise adjustment mechanism 300 includes a body 310, a plunger 320, and a spring
330. The precise adjustment mechanism 300 may be fixed to the strut body 110 in a
position that does not interfere with the adjustment scale and, in one embodiment,
may be positioned underneath the threaded collar 250 as generally shown in FIGS. 1A-1C.
In use, the spring 330 biases the plunger 320 so that the plunger 320 extends beyond
an outer edge of the body 310 and into the cavity 252 of the threaded collar 250.
Thus arranged, the precise adjustment mechanism 300 cannot turn as long as the plunger
320 is positioned within the cavity 252 of the threaded collar 250. Moving the plunger
320 from its first position to a second position so that the plunger 320 no longer
engages the threaded collar 250 allows the precise adjustment mechanism 300 to be
turned, advancing or retrieving the threaded rod 120 relative to the strut body 110
and hence adjusting the length of the external fixation strut 100. The number and
spacing of cavities 252 in the base of the threaded collar 250 defines the resolution
of precise adjustment. For example, four equally spaced cavities 252 with an assembly
that advances one millimeter per full turn provides tactile feel and hard stops every
quarter of a turn of adjustment, which are one-quarter millimeter linear adjustment
increments. When fully assembled, the threaded collar 250 turns with the actuator
body 210 as one assembly. In other embodiments, the body 310, or a similar component,
may be coupled to the strut body and notches, openings, or other mechanisms may be
located on the actuator body.
[0056] In one example of an embodiment, as will be described in greater detail, the external
fixation struts 100 may be coupled to first and second rings, bases, etc. (used interchangeably
without the intent to limit), as will be appreciated by one of ordinary skill in the
art. The external fixation struts 100 may be coupled to the bases by any suitable
connectors, mechanisms, or the like now known or hereafter developed. For example,
referring to FIGS. 7A and 7B, U-joints 500 may be used. Alternatively however, as
previously mentioned, any other now known or hereafter developed connector can be
used such as, for example, ball joints, threaded ends, etc. In one example of an embodiment,
each of the U-joints 500 may be constructed of two joint clevises 510, 512, a central
body 514, and set screws 516. The set screws 516 connect the central body 514 to the
joint clevises 510, 512 and reduce the slope of the joints. That is, one or more of
the U-joints for coupling the external fixator struts may include first and second
clevis components 510, 512, each clevis component 510, 512 having a threaded bore
for receiving a fastener for coupling the first and second clevis components 510,
512 to, for example, the external fixator strut and the base, ring, etc. In addition,
the one or more of the U-joints may include a central body or bushing 514 having a
plurality of openings such as, for example, threaded openings for receiving a plurality
of screws such as, for example, set screws, ball end screws, etc. for coupling the
central body or bushing 514 to the first and second clevis components 510, 512.
[0057] Alternative embodiments of the disengagement members, labelled 230' and 230", are
depicted in FIGS. 8A and 8B. The disengagement member 230' shown in FIG. 8A has angled
exterior surfaces 239 so that both disengagement members 230' may be depressed by
portions of the rotating sleeve 240 as the rotating sleeve 240 is rotated relative
to the actuator body 210. As seen in FIG. 8B, the disengagement member 230" may be
designed without the angled exterior surfaces, thus requiring the disengagement members
be depressed before the sleeve 240 can be rotated relative to the actuator body 210.
[0058] As shown in FIGS. 9A-9D, an alternative embodiment of the acute adjustment mechanism
may have an alternative actuator body 2210 with a different gripping surface and an
alternative rotating sleeve 2240 with round openings 2260 rather than rectangular
openings. The alternative actuator body 2210 is shown in use with disengagement members
230". In FIGS. 9A and 9B, the rotating sleeve 2240 is shown with its openings 2260
aligned with disengagement members 230" to allow the mobile jaws 220 to be pushed
against the spring bias and engaged with the threaded rod 120. As shown in FIGS. 9C
and 9D, the rotating sleeve 2240 is moved rotationally to block outward travel of
the disengagement members 230" and hold the disengagement members 230" in a pushed
state that disengages the mobile jaws 220 from the threaded rod 120.
[0059] Referring to FIG. 10, in one example of an embodiment, the external fixation strut
100 may also include a locking sleeve 600. In use, incorporation of the locking sleeve
600 may assist with preventing accidental adjustment for any of the fixation strut
embodiments disclosed herein. In this embodiment of the locking sleeve, adjustment
would be limited to motion of a tracer pin 610 with the locking sleeve 600 coupled
around the strut body 110. The locking sleeve 600 may be held in place at the desired
level with a bolt 620 that may be engaged with the side of the strut body 110. This
prevents the strut 100 from adjusting but does not take up any adjustment range of
the threaded rod 120. That is, in one example of an embodiment, the a tracer pin 610
may be operatively coupled to the threaded rod 120. The tracer pin 610 can be coupled
to the threaded rod 120 by any now known or hereafter developed mechanism including,
for example, adhesive, welding, fasteners, integrally formed, etc. The locking sleeve
600 may be operatively and selectively coupled to the strut body 110 by any now known
or hereafter developed mechanism such as, for example, bolt 620. The locking sleeve
600 includes an opening, cavity, or the like, arranged and configured to receive the
tracer pin 610. In use, the locking sleeve 600 is arranged and configured to prevent
movement of the track pin 610 and thus to prevent adjustment of the external fixation
strut.
[0060] As previously mentioned, in use, the external fixation strut 100 may be a part of
an external fixation system that includes an upper base, a lower base, and multiple
struts between the upper base and the lower base. At least one of the struts may be
the external fixation strut 100 or one of the other fixation struts disclosed herein.
In some embodiments, the system includes six struts coupled between the upper base
and the lower base and at least one of the six struts is the external fixation strut
100, but in other embodiments may include systems with fewer or more struts than six.
Any of the struts described herein may also include one or more telescoping bodies
that translate relative to one another to change the overall length of the strut.
The system may also include connectors for coupling with one or both of the upper
base and the lower base. For example, the connectors may include the universal joints
500 and further may include fasteners between the universal joints 500 and the bases.
System embodiments may also include bone fixation mechanisms for coupling between
the connectors or the bases and tissue of a patient. Such bone fixation mechanisms
may be any now known or hereafter developed bone fixation members including, for example,
wires (threaded and unthreaded), k-wires, pins, and screws.
[0061] Referring to FIGS. 11A-16, an alternate example of an embodiment of an external fixation
strut 1100 is disclosed. As will be described herein, external fixation strut 1100
may be substantially similar to external fixation strut 100 except as noted herein.
As shown in the example embodiment, the external fixation strut 1100 includes a strut
body 1110, a threaded rod 120 substantially rotationally fixed relative to the strut
body 1110 so that movement of the threaded rod 120 axially translates or moves the
threaded rod 120 relative to the strut body 1110, an acute adjustment mechanism 1200
selectively disengageable from threads of the threaded rod 120, and a precise adjustment
mechanism 1300.
[0062] In one example of an embodiment, the acute adjustment mechanism 1200 includes an
actuator body 1210 that includes a threaded collar 1250 (FIGS. 12 and 14B), a spring-loaded
mobile jaw 1220 including associated biasing springs 1214, and one or more disengagement
members 1230 that are configured to interact with the mobile jaw 1220. The actuator
body 1210 includes one or more apertures 1216 (FIGS. 13C and 14A) to receive at least
a portion of the one or more disengagement members 1230, respectively (e.g., as shown,
the acute adjustment mechanism 1200 may include one disengagement member 1230 and
one aperture 1216). The disengagement member 1230 may be in the form of shown is a
button capable of translation toward the center of the device and rotation about its
axis, but other embodiments are envisioned including, for example, one or more wedges,
screws, cams, or any other mechanism now known or hereafter developed.
[0063] In the illustrated embodiment, the threaded collar 1250 is arranged and configured
to couple the actuator body 1210 to the strut body 1110. In one example of an embodiment,
the actuator body 1210 may include one or more channels 1212 (FIG. 16) to guide the
path of the mobile jaws 1220 and the associated springs 1214. In use, the associated
springs 1214 bias the mobile jaws 1220 against the threaded rod 120 and toward the
disengagement member 1230. For example, the mobile jaws 1220 may include faces 1222
that interact with surfaces 1232 of the disengagement member 1230 so that when the
disengagement member 1230 is pressed inward, the mobile jaws 1220 move (e.g., separate
and disengage) from the threaded rod 120 so that the strut length of the external
fixation strut 1100 can be adjusted acutely.
[0064] In one example of an embodiment, as shown, the precise adjustment mechanism 1300
includes a body 1310, a pivot pin 1340, and a spring 1330. The spring 1330 biases
the body 1310 about the pivot pin 1340 to an engaged position toward a notch 1180
(FIG. 15C) in the strut body 1110. In use, the actuator body 1210 is inhibited from
moving (e.g., turning) relative to the strut body 1110 as long as a portion of the
body 1310 is seated in the notch 1180.
[0065] In one example of an embodiment, as shown, the external fixation strut 1100 may also
include bands 1400, as described herein. In addition, and/or alternatively, the external
fixation strut 1100 may also include and one or more connectors 500 to couple the
external fixation strut 1100 to one or more bases. As shown, and as previously mentioned,
the connectors 500 may be in the form of a U-joint, alternatively however any other
now known or hereafter developed connector can be used such as, for example, ball
joints, threaded ends, etc.
[0066] In the illustrated embodiment, the mobile jaws 1220 are biased to couple with the
threads of the threaded rod 120 by the springs 1214. The mobile jaws 1220 shown include
threaded portions that interact with the threaded rod 120, but in other embodiments,
mobile jaws may include other structure for interacting with the threaded rod including,
for example, knurling, a softer material, or any other structure or material that
is capable of interacting with the threads of the threaded rod 120. In use, the mobile
jaws 1220 are arranged and configured to interact with the disengagement members 1230.
For example, the mobile jaws 1220 may include faces 1222 that interact with surfaces
1232 of the disengagement member 1230. Aperture 1216 formed in the side of the actuator
body 1210 may constrain the disengagement member 1230. In use, the disengagement member
1230 is designed so that it can be pressed from outside of the actuator body 1210
toward the threaded rod 120 so that when the disengagement member 1230 is pressed
inwards, the mobile jaws 1220 disengage from the threaded rod 120 enabling the strut
length of the external fixation strut 100 to be adjusted acutely. For example, in
one embodiment, the geometry of the disengagement member 1230 inside of the actuator
body 1210 may be shaped like a wedge, although other suitable configurations are envisioned.
The faces 1232 of this wedge interact with the faces 1222 of the mobile jaws 1220
so that when the disengagement member 1230 is pressed inward, the mobile jaws 1220
move (e.g., separate and disengage) from the threaded rod 120 (FIGS. 13E-14B) enabling
the threads to be disengaged and hence the strut length to be adjusted acutely. As
shown in the progression between FIGS. 13D and 13E and with the action arrows in FIG.
13E, the mobile jaws 1220 are configured to pivot away from the threaded rod 120 when
sufficiently interacted with by the disengagement member 1230.
[0067] The mobile jaws 1220 may be constrained within the actuator body 1210 by the channels
1212 (FIG. 16) so that pivoting toward and away from the threaded rod 120 is accomplished
along a designated path. As shown in the progression between FIG. 13E and FIGS. 14A-14B,
the disengagement member 1230 is configured to be rotated about its longitudinal axis
to engage tabs 1233 behind a portion of the actuator body 1210 when the disengagement
member 1230 has been pressed toward the threaded rod 120. By rotating multiple disengagement
members on multiple external fixation struts in this manner, multiple external fixation
struts can be adjusted acutely at once because the user is not required to keep the
disengagement member 1230 depressed by hand.
[0068] As previously mentioned, the external fixation strut 1100 may also include a threaded
collar 1250 (FIGS. 12 and 14B). In use, the threaded collar 1250 connects the actuator
body 1210 to the strut body 1110. The threaded collar 1250 may be slid up the base
of the strut body 1110 and threaded into the base of the actuator body 1210. As shown,
the acute adjustment mechanism 1200 may also include a first washer 1280 and a second
washer 1282 (FIG. 12). Washers 1280, 1282 (FIG. 12) may be positioned between the
threaded collar 1250 and the strut body 1110, and between the strut body 1110 and
the actuator body 1210. The washers 1280, 1282 act as spacers and reduce friction.
The washer 1282 between the strut body 1110 and the actuator body 1210 may also further
constrain the mobile jaws 1220 and disengagement member 1230. In the illustrated embodiment,
the mobile jaws 1220may be constrained within the acute adjustment mechanism 1200
by the channels 1212 (FIG. 16). Each of the channels 1212 inside the actuator body
1210 may correspond to (e.g., match) a protrusion 1224 (FIGS. 14B, 15C, and 15E) on
the top of the mobile jaws 1220. Thus arranged, rotation of the mobile jaws 1220 is
guided toward and away from the threaded rod 120 and prevents the mobile jaws 1220
from moving out of position. Alternatively, jaws of some embodiments may have posts
on the jaws that align with holes on the actuator body and the rotating sleeve.
[0069] Referring to FIGS. 12, 13A, and 15A, as previously mentioned, the external fixation
strut 1100 may also include a band 1400. In some embodiments, bands 1400 may be arranged
and configured as identification (ID) bands for identifying each particular strut
in the external fixation system. As such, the bands 1400 may be provided to numerically
identify strut assemblies so that each strut assembly may be distinguished for a prescription.
In use, the bands 1400 are coupled to the external fixation struts 1100. For example
as shown, in one example of an embodiment, the bands 1400 may be slid down over the
top of the actuator body 1210. Some embodiments of the band 1400 include pegs, projections,
or other connection devices that are sized and configured to be received by holes
in an associated actuator body to couple the components. The band 1400 provides a
safety feature and reduces the risk of inadvertent acute adjustment of the strut assembly
by limiting access to the disengagement member 1230, making it more difficult to inadvertently
depress. Acute adjustment generally takes place clinically during application of the
external fixation frame or during strut change-outs. The bands 1400 may be helpful
to avoid inadvertent acute adjustment when a patient is adjusting struts using precise
adjustment mechanisms to comply with an adjustment prescription such as, for example,
when adjusting the struts at home utilizing the precise adjustment mechanism to comply
with the prescription.
[0070] Referring to FIGS. 15A-15E, the precise adjustment mechanism 1300 will be described
in greater detail. As will be described in greater detail, the precise adjustment
mechanism 1300 enables the strut length of the external fixation struts 1100 to be
adjusted. As noted above, the spring 1330 biases the body 1310 about the pivot pin
1340 to an engaged position toward the notch 1180 (FIG. 15C and 15E) in the strut
body 1110. Thus arranged, the body 1310 cannot turn relative to the strut body 1110
as long as a portion of the body 1310 is seated in the notch 1180. Moving the body
1310 about the pivot pin 1340 in the direction of the action arrows in FIGS. 15D and
15E from a first position to a second position so that the body 1310 is no longer
positioned in the notice 1180 allows for the precise adjustment mechanism 1300 to
be turned with the acute adjustment mechanism 1200, advancing or retrieving the threaded
rod 120 (e.g., the acute and precise adjustment mechanisms 1200, 1300 are fixed within
the actuator body 1210. As such, when the actuator body turns to adjust small increments
(e.g., via the precise adjustment mechanism) the components of both mechanisms turn
in unison). The number and spacing of the notches 1180 defines the resolution of precise
adjustment. For example, four equally spaced notches 1180 with an assembly that advances
one millimeter per full turn provides tactile feel and hard stops every quarter of
a turn of adjustment, which are one-quarter millimeter linear adjustment increments.
When fully assembled, the threaded collar 1250 (FIG. 14B) turns with the actuator
body 1210 as one assembly. In other embodiments, the body 1310, or a similar component,
may be coupled to the strut body and notches, openings, or other mechanisms may be
located on the actuator body.
[0071] Although not shown, the external fixation strut 1100 may also include a locking sleeve
such as, for example, the locking sleeve 600 described above in association with FIG.
10. In use, incorporation of the locking sleeve 600 may assist with preventing accidental
adjustment. In this embodiment, and as previously mentioned, adjustment would be limited
to motion of the tracer pin 610 with the locking sleeve 600 coupled around the strut
body 1110. The locking sleeve 600 may be held in place at the desired level with the
bolt 620 that may be engage with the side of the strut body 1110. This prevents the
strut from adjusting but does not take up any adjustment range of the threaded rod
120.
[0072] The external fixation strut 1100 may be a part of an external fixation system that
includes an upper base, a lower base, and multiple struts between the upper base and
the lower base. At least one of the struts may be the external fixation strut 1100
or one of the other fixation struts disclosed herein. In some embodiments, the system
includes six struts coupled between the upper base and the lower base and at least
one of the six struts is the external fixation strut 1100, but in other embodiments
may include systems with fewer or more struts than six. Any of the struts described
herein may also include one or more telescoping bodies that translate relative to
one another to change the overall length of the strut. The system may also include
connectors for coupling with one or both of the upper base and the lower base. For
example, the connectors may include the universal joints 500 and further may include
fasteners between the universal joints 500 and the bases. System embodiments may also
include bone fixation mechanisms for coupling between the connectors or the bases
and tissue of a patient. Such bone fixation mechanisms may include wires (threaded
and unthreaded), k-wires, pins, and screws, for example.
[0073] Referring to FIGS. 17-18D, an alternate example of an embodiment of an external fixation
strut 3100 is disclosed. As will be described herein, external fixation strut 3100
may be substantially similar to external fixation struts 100, 1100 except as noted
herein. As shown, the external fixation strut 3100 includes a strut body 1110, a threaded
rod 120 substantially rotationally fixed relative to the strut body 1110 so that movement
of the threaded rod 120 axially translates or moves the threaded rod 120 relative
to the strut body 1110, an acute adjustment mechanism 3200 selectively disengageable
from threads of the threaded rod 120, and a precise adjustment mechanism such as,
for example, the precise adjustment mechanism 1300.
[0074] In one example of an embodiment, the acute adjustment mechanism 3200 includes an
actuator body 3210 that includes the threaded collar 1250 (FIGS. 18B and 18D), a spring-loaded
mobile jaw 3220, and one or more disengagement members 3230 that are configured to
interact with the mobile jaw 3220. The disengagement member 3230 includes structure
arranged and configured to interact with the mobile jaws 3220. For example, the disengagement
members 3230 may include a structure with an arcuate surface 3232 (FIG. 18D) facing
the mobile jaws 3220 configured to move away from and toward the center of the device,
but other embodiments are envisioned including, for example, a disengagement member
including one or more wedges, screws, cams, or any other mechanism now known or hereafter
developed.
[0075] In the illustrated embodiment, the external fixation struct 3100 may include a threaded
collar such as, for example, the threaded collar 1250, to connect the actuator body
3210 to the strut body 1110. In one example of an embodiment, the actuator body 3210
may include one or more channels to guide the path of the mobile jaws 3220. In the
embodiment depicted, each of the mobile jaws 3220 is hinged about a pin 1112 (FIGS.
18B and 18D). The illustrated mobile jaws 3220 include torsion springs 3221 (FIGS.
18B and 18D) that bias the mobile jaws 3220 away from the threaded rod 120 and toward
the disengagement member 3230. The mobile jaws 3220 have faces 3222 (FIG. 18D) that
interact with the arcuate surface 3232 of the disengagement member 3230 so that when
the disengagement member 3230 is allowed to move away from the center of the device
(e.g., when the disengagement member is allowed to move the first position to the
second position), the faces 3222 of the mobile jaws press against the arcuate surface
3232 and the mobile jaws 3220 move (e.g., separate and disengage) from the threaded
rod 120 (FIGS. 18C and 18D) so that the strut length of the external fixation strut
3100 can be adjusted acutely.
[0076] In one example of an embodiment, the precise adjustment mechanism may be the precise
adjustment mechanism 1300 previously described. As previously described, the precise
adjustment mechanism 1300 includes a body 1310, a pivot pin 1340, and a spring. The
spring biases the body 1310 about the pivot pin 1340 to an engaged position toward
a notch 1180 (FIGS. 18B and 18D) in the strut body 1110. The body 1310 cannot turn
relative to the strut body 1110 as long as a portion of the body 1310 is seated in
the notch 1180.
[0077] In one example of an embodiment, the external fixation strut 3100 may also include
bands 3400 (FIGS. 17, 18A, and 18C) as described herein. In addition, and/or alternatively
the external fixation strut 3100 may include and one or more connectors 500 to couple
the external fixation strut 3100 to one or more bases. As shown, and as previously
mentioned, the connectors 500 may be in the form of a U-joint, alternatively however
any other now known or hereafter developed connector can be used such as, for example,
ball joints, threaded ends, etc. In some embodiments, the band 3400 may be considered
a containment device that is a component of the disengagement member that works in
conjunction with the disengagement member 3230 to hold the disengagement member 3230
toward the center of the device to cause the mobile jaws 3220 to engage with the threaded
rod 120 (e.g., the band/containment device are arranged and configured to hold the
disengagement member in the first position so that the mobile jaws engage the threaded
rod).
[0078] In use, the mobile jaws 3220 of this embodiment are both biased to decouple from
the threads of the threaded rod 120 by the torsion springs 3221. The mobile jaws 3220
shown include threaded portions that interact with the threaded rod 120, but in other
embodiments, mobile jaws may include other structure for interacting with the threaded
rod including, for example, knurling, a softer material, or any other structure or
material that is capable of interacting with the threads of the threaded rod 120.
In use, the mobile jaws 3220 are arranged and configured to interact with the disengagement
member 3230. For example, the mobile jaws 3220 may include faces 3222 that interact
with the arcuate surface 3232 of the disengagement member 3230. In use, the disengagement
member 3230 is designed so that it can be pressed toward the center of the device
and toward the threaded rod 120 when the band 3400 is removed. The band 3400 may then
be returned to position on the device, as shown in FIGS. 17 and 18A to keep the mobile
jaws 3220 engaged with the threaded rod 120 (e.g., to hold the disengagement member
in the first position so that the mobile jaws engage the threaded rod).
[0079] As shown in the progression between FIGS. 18A and 18C and with the action arrows
in FIG. 18C, the mobile jaws 3220 are configured to pivot away from the threaded rod
120 when the band 3400 is removed from the device and the disengagement member 3230
is allowed to move away from the center of the device (e.g., the mobile jaws 3220
are arranged and configured to move from a first position to a second position wherein
the mobile jaws move away (e.g., disengage) from the threaded rod 120 when the band
3400 is removed from the device and the disengagement member 3230 is allowed to move).
Once the threads are disengaged, the strut length can be adjusted acutely. As shown
in the progression between FIGS. 18A-18B and FIGS. 18C-18D, the disengagement member
3230 is biased to a disengaged state in the absence of the band 3400. By removing
multiple bands 3400 on multiple external fixation struts, multiple external fixation
struts can be adjusted acutely at once on an external fixation system.
[0080] Band 3400 placement is depicted in FIGS. 17 and 18A. In some embodiments, bands 3400
may be arranged and configured as identification (ID) bands for identifying each particular
strut in the external fixation system. As such, the bands 3400 may be provided to
numerically identify strut assemblies so that each strut assembly may be distinguished
for a prescription. The bands 3400 shown slide down over the top of the actuator body
3210. In use, the bands 3400 are coupled to the external fixation struts 3100. For
example, as shown, in one example of an embodiment, the band 3400 include pegs, projections,
or other connection devices that fit in holes in an associated actuator body to couple
the components. The band 3400 provides a safety feature and reduces the risk of inadvertent
acute adjustment of the strut assembly by limiting movement of the disengagement member
3230. As previously mentioned, acute adjustment generally takes place clinically during
application of the external fixation frame or during strut change-outs. The bands
3400 may be helpful to avoid inadvertent acute adjustment when a patient is adjusting
struts using precise adjustment mechanisms to comply with an adjustment prescription.
[0081] Although not shown, the external fixation strut 3100 may also include a locking sleeve
such as, for example, the locking sleeve 600 described above in association with FIG.
10. Use of such a device is an option for preventing accidental adjustment.
[0082] The external fixation strut 3100 may be a part of an external fixation system that
includes an upper base, a lower base, and multiple struts between the upper base and
the lower base. At least one of the struts may be the external fixation strut 3100
or one of the other fixation struts disclosed herein. In some embodiments, the system
includes six struts coupled between the upper base and the lower base and at least
one of the six struts is the external fixation strut 3100, but in other embodiments
may include systems with fewer or more struts than six. Any of the struts described
herein may also include one or more telescoping bodies that translate relative to
one another to change the overall length of the strut. The system may also include
connectors for coupling with one or both of the upper base and the lower base. For
example, the connectors may include the universal joints 500 and further may include
fasteners between the universal joints 500 and the bases. System embodiments may also
include bone fixation mechanisms for coupling between the connectors or the bases
and tissue of a patient. Such bone fixation mechanisms may include wires (threaded
and unthreaded), k-wires, pins, and screws, for example.
[0083] Referring to FIGS. 19-21B, an alternate example of an embodiment of an external fixation
strut 4100 is disclosed. As will be described herein, external fixation strut 4100
may be substantially similar to external fixation strut 100, 1100, 3100 except as
noted herein. As shown, the external fixation strut 4100 includes a strut body 1110,
a threaded rod 120 substantially rotationally fixed relative to the strut body 1110
so that movement of the threaded rod 120 axially translates or moves the threaded
rod 120 relative to the strut body 1110, an acute adjustment mechanism 4200 selectively
disengageable from threads of the threaded rod 120, and a precise adjustment mechanism
such as, for example, the precise adjustment mechanism 1300.
[0084] In one example of an embodiment, the acute adjustment mechanism 4200 includes an
actuator body 4210 that includes a threaded collar 1250 (FIGS. 20D, 20E, and 20G),
a spring-loaded mobile jaw 4220, and one or more disengagement members 4230 that are
configured to interact with the mobile jaw 4220. The disengagement member 4230 may
be in the form of a button capable of translation toward the center of the device,
but other embodiments are envisioned including, for example, one or more wedges, screws,
cams, or any other mechanism now known or hereafter developed.
[0085] In use, the threaded collar 1250 is arranged and configured to couple the actuator
body 4210 to the strut body 1110. In one example of an embodiment, the actuator body
4210 may include one or more channels to guide the path of the mobile jaws 4220. The
device may include springs configured to bias the mobile jaws 4220 against the threaded
rod 120 and toward the disengagement member 4230. As shown in FIGS. 20E and 20G, the
mobile jaws 4220 may include faces 4222 that interact with surfaces 4232 of the disengagement
member 4230 so that when the disengagement member 4230 is pressed inward, the mobile
jaws 4220 move (e.g., are separate and disengage) from the threaded rod 120 so that
the strut length of the external fixation strut 4100 can be adjusted acutely.
[0086] In one example of an embodiment, the precise adjustment mechanism may be the precise
adjustment 1300 previously described. As previously described, the precise adjustment
mechanism 1300 includes a body 1310, a pivot pin 1340, and a spring. The spring biases
the body 1310 about the pivot pin 1340 to an engaged position toward a notch 1180
(FIGS. 20D, 20E, and 20G) in the strut body 1110. In use, the body 1310 is inhibited
from moving (e.g., turning) relative to the strut body 1110 as long as a portion of
the body 1310 is seated in the notch 1180.
[0087] In one example of an embodiment, the external fixation strut 4100 may also include
bands 4400 as described herein. In addition, and/or alternatively, the external fixation
strut 4100 may include one or more connector 500 to couple the external fixation strut
4100 to one or more bases. As shown, and as previously mentioned, the connectors 500
may be in the form of a U-joint, alternatively however any other now known or hereafter
developed connector can be used such as, for example, ball joints, threaded ends,
etc.
[0088] In use, in the illustrated embodiment, the mobile jaws 4220 are both biased to couple
with the threads of the threaded rod 120 by the springs or other biasing mechanisms.
For example, in one embodiment, the springs could be torsion springs that fit over
either or both of the pins 1112, as shown in FIG. 18B, or any other effective biasing
force member. The mobile jaws 4220 shown include threaded portions that interact with
the threaded rod 120, but other embodiments are envisioned including, for example,
knurling, a softer material, or any other structure or material that is capable of
interacting with the threads of the threaded rod 120. In use, the mobile jaws 4220
are arranged and configured to interact with the disengagement member 4230. For example,
the mobile jaws 4220 may include faces 4222 that interact with surfaces 4232 of the
disengagement member 4230. Aperture 4216 (FIGS. 20B and 20F) formed in the side of
the actuator body 4210 may constrain the disengagement member 4230. In use, the disengagement
member 4230 is designed so that it can be pressed from outside of the actuator body
4210 toward the threaded rod 120 (action arrow in FIG. 20F) so that when the disengagement
member 4230 is pressed inward (e.g., when the disengagement member 4230 is moved from
a first position to a second position), the mobile jaws 4220 disengage from the threaded
rod 120 enabling the strut length of the external fixation strut 4100 to be adjusted
acutely. For example, in one embodiment, the geometry of the disengagement member
4230 inside of the actuator body 4210 may be shaped like a wedge, although other suitable
configurations are envisioned. The faces of the wedge interact with the faces 4222
of the mobile jaws 4220 so that when the disengagement member 4230 is pressed inward,
the mobile jaws 4220 move (e.g., separate and disengage) from the threaded rod 120
(FIGS. 20F and 20G) enabling the threads to disengage, and the strut length to be
adjusted acutely. In the embodiment shown, the mobile jaws 4220 are configured to
pivot away from the threaded rod 120 when sufficiently interacted with by the disengagement
member 4230.
[0089] The mobile jaws 4220 may be constrained within the actuator body 4210 by channels
so that pivoting toward and away from the threaded rod 120 is accomplished along a
designated path. Control of the pivoting path may also or alternatively be directed
by pivoting about respective pins 1112 (FIGS. 20D, 20E, and 20G). As shown in FIG.
21A, and as will be described in greater detail below, after the disengagement member
4230 has been pressed toward the threaded rod 120, the disengagement member 4230 may
be held in this position by a temporary or acute band 4499 positionable on the external
fixation struts. By installing multiple temporary or acute bands 4499 on multiple
external fixation struts in this manner, multiple external fixation struts can be
adjusted acutely at once because the user is not required to keep the disengagement
members 4230 depressed by hand, as will be described in greater detail below.
[0090] Band 4400 placement is depicted in FIGS. 19, 20A, and 20D. In some embodiments, bands
4400 may be arranged and configured as identification (ID) bands for identifying each
particular strut in the external fixation system. As such, the bands 4400 may be provided
to numerically identify strut assemblies so that each strut assembly may be distinguished
for a prescription. The bands 4400 shown slide in and out from a side of the actuator
body 4210, as shown in FIG. 20B, although other configurations are envisioned. In
use, the bands 4400 are coupled to the external fixation struts 4100. For example,
as shown, in one example of an embodiment, the band include pegs, projections, or
other connection devices that fit in holes in an associated actuator body to couple
the components. For example, the illustrated band 4400 includes arms 4455 (FIGS. 20B,
20C, and 20D) configured to pass through slots 4255 (FIGS. 20B and 20F) and engage
with the mobile jaws 4220 within the actuator body to hold the mobile jaws 4220 against
the threaded rod 120.
[0091] The band 4400 may also act as a safety feature by reducing the risk of inadvertent
acute adjustment of the strut assembly by limiting access to the disengagement member
4230. For example, in the illustrated embodiment, the band 4400 is arranged and configured
to fit over the actuator body 4210 without pushing, moving, activating, etc. the disengagement
member 4230. As such, the band 4400 is arranged and configured to engage the actuator
body 4210 without activating the disengagement member 4230 and thus preventing a patient
from disengaging the mobile jaws 4220 from the threaded rod 120. As shown, in the
illustrated embodiment, the band 4400 includes a recess 4416 arranged and configured
to align with and receive the disengagement member 4230 so that the disengagement
member 4230 is received within the recess 4416 when the band 4400 is coupled to the
actuator body 4210 (e.g., the recess 4416 formed in the band 4400 allows the band
4400 to be fully seated on the actuator body 4210 without pushing the disengagement
member (e.g., button) 4230). In use, the arms 4455 of the band 4400 contact and fix
the position of the mobile jaws 4220 thereby prohibiting, or at least minimizing,
patient access to the disengagement member (e.g., button) 4230 while band 4400 is
coupled to the actuator body 4210.Thus arranged, the band 4400 makes it more difficult
to inadvertently depress the disengagement member 4230. As previously mentioned, acute
adjustment generally takes place clinically during installation of the external fixation
frame or during strut change-outs. The bands 4400 may be helpful to avoid inadvertent
acute adjustment when a patient is adjusting struts using precise adjustment mechanisms
to comply with an adjustment prescription.
[0092] As noted above, temporary or acute bands 4499 may be used to hold the disengagement
member 4230 in place during acute adjustment of a strut. That is, in contrast to the
bands such as, for example, band 4400 described above, the temporary or acute band
4499 shown in FIGS. 21A and 21B are arranged and configured to ensure that the disengagement
member (e.g., button) 4230 is activated, pressed, etc. Thus arranged, in use, surgeons
can place, engage, etc. a temporary or acute band 4499 on each strut to change the
length of a strut freely without having to push in each disengagement member. In this
way, surgeons can, for example, have all six struts unlocked at once to adjust a frame
acutely. In one example of an embodiment, this can be accomplished by providing a
temporary or acute band 4499 without a recess. That is, by eliminating the recess
4416 from band 4400 that is sized and shaped to allow the disengagement member 4230
to not be depressed when the band 4400 is in place on the device, temporary or acute
band 4499 contacts and activates the disengagement member 4230 when the temporary
or acute band 4499 is coupled to the actuator body. Respective temporary or acute
bands 4499 may have an essentially similar geometric configuration as compared to
the bands 4400, except for elimination of the recess 4416 and changes to the arms
4455, and may have similar or the same respective size markings or colorings as the
bands 4400. Regarding changes to the arms, see temporary arms 4465 in FIG. 21B that
are shorter and more lateral and do not contact the mobile jaws 4220 sufficiently
to press the mobile jaws 4220 against the threaded rod 120. A lack of the recess 4416
is also evident in the view presented in FIG. 21B, as well as FIG. 21A. Embodiments
of the temporary or acute bands 4499 may also include a retention structure, such
as a tab 4488 shown in FIGS. 20C, 20D, and 21B, useful in resisting inadvertent disengagement
of the temporary or acute bands 4499 from an actuator body.
[0093] As previously mentioned, once the disengagement member 4230 has been pressed toward
the threaded rod 120, the disengagement member 4230 may be held in this position by
a temporary or acute band 4499. By installing multiple temporary or acute bands 4499
on multiple external fixation struts in this manner, multiple external fixation struts
can be adjusted acutely at once because the user (e.g., surgeon during initial installation,
strut change-out, etc.) is not required to individually press and hold each disengagement
member 4230 in the pressed or activated position. Referring to FIGS. 22A-22D, an alternate
example embodiment of a temporary or acute band 4499' is disclosed. Temporary or acute
band 4499' is substantially similar to temporary or acute band 4499. In use, temporary
or acute band 4499' may be used in connection with an external fixator strut disclosed
herein. In use, temporary or acute band 4499' is arranged and configured to hold the
disengagement member such as, for example, disengagement member 4230 in place during
acute adjustment of the strut. In the illustrated embodiment, this can be accomplished
by eliminating the recess 4416 that is sized and shaped to allow band 4400 to be coupled
to the external fixation strut without depressing the disengagement member 4230 when
the band is placed on the device. Respective temporary or acute bands 4499' may have
an essentially similar geometric configuration, except for elimination of the recess
4416 and changes to the arms 4455, and may have similar or the same respective size
markings or colorings as the bands 4400. Regarding changes to the arms, see temporary
arms 4465' that are shorter and more lateral and do not contact the mobile jaws 4220
sufficiently to press the mobile jaws 4220 against the threaded rod 120. A lack of
the recess 4416 is also evident in the view presented in FIG. 22A. Embodiments of
temporary or acute bands may also include a retention structure, such as a tab, useful
in resisting inadvertent disengagement of the temporary or acute band from the actuator
body.
[0094] Although not shown, the external fixation strut 4100 may also include a locking sleeve
such as, for example, the locking sleeve 600 described above in association with FIG.
10. Use of such a device is an option for preventing accidental adjustment.
[0095] The external fixation strut 4100 may be a part of an external fixation system that
includes an upper base, a lower base, and multiple struts between the upper base and
the lower base. At least one of the struts may be the external fixation strut 4100
or one of the other fixation struts disclosed herein. In some embodiments, the system
includes six struts coupled between the upper base and the lower base and at least
one of the six struts is the external fixation strut 4100, but in other embodiments
may include systems with fewer or more struts than six. Any of the struts described
herein may also include one or more telescoping bodies that translate relative to
one another to change the overall length of the strut. The system may also include
connectors for coupling with one or both of the upper base and the lower base. For
example, the connectors may include the universal joints 500 and further may include
fasteners between the universal joints 500 and the bases. System embodiments may also
include bone fixation mechanisms for coupling between the connectors or the bases
and tissue of a patient. Such bone fixation mechanisms may include wires (threaded
and unthreaded), k-wires, pins, and screws, for example.
[0096] An example, outside the scope of the claims, is a method of adjusting an external
fixation strut, such as the external fixation struts 100, 1100, 4100. Such a method
may include disengaging an acute adjustment mechanism 200, 1200, 4200 of the external
fixation strut 100, 1100, 4100 from threads formed on a threaded rod 120 of the external
fixation strut 100, 1100, 4100. The acute adjustment mechanism 200, 1200, 4200 may
be biased toward an engaged state in some illustrated embodiments. The threaded rod
120 may be substantially rotationally fixed relative to a strut body 110, 1110 of
the external fixation strut 100, 1100, 4100 so that movement of the threaded rod 120
axially translates or moves the threaded rod 120 relative to the strut body 110, 1110.
In some embodiment, the threaded rod 120 may be substantially rotationally fixed relative
to a strut body 110, 1110 of the external fixation strut 100, 1100, 4100 by, for example,
the tracer pin 610 shown in FIG. 10. In the illustrated embodiments, disengaging the
acute adjustment mechanism 200, 1200, 4200 of the external fixation strut 100, 1100
from threads formed on the threaded rod 120 includes moving mobile jaws 220, 1220,
4220 from the threaded rod 120. For example, disengaging the acute adjustment mechanism
200, 1200, 4200 may include separating two substantially oppositely positioned mobile
jaws 220, 1220, 4220 from one another. Referring to FIGS. 1A-10, in the embodiment
shown with mobile jaws 220, separating the two substantially oppositely positioned
mobile jaws 220 includes moving (e.g., translating) the mobile jaws 220 away from
the threaded rod 120. In this embodiment, the two substantially oppositely positioned
mobile jaws 220 are moved by forcing the disengagement members 230 into contact with
both of the mobile jaws 220, as shown by the action arrows in FIG. 3F.
[0097] Referring to FIGS. 11A-16 and 19-21B, in the embodiments shown with mobile jaws 1220
and 4220 respectively, separating the two substantially oppositely positioned mobile
jaws 1220, 4220 includes moving (e.g., rotating) the mobile jaws 1220, 4220 away from
the threaded rod 120. In these embodiments, the two substantially oppositely positioned
mobile jaws 1220, 4220 are moved by forcing the disengagement member 1230, 4230 into
contact with both of the mobile jaws 1220, 4220, as shown by the action arrows in
FIG. 13E and FIGS. 20F. The opposite ends of the mobile jaws 1220 from the ends where
the mobile jaws 1220 are contacted by the disengagement member 1230 are configured
to contact respective surfaces of the actuator body 1210 and pivot against those surfaces.
The mobile jaws 4220 pivot about pins 1112 at their opposite ends from the ends where
the mobile jaws 4220 are contacted by the disengagement member 4230.
[0098] Methods of adjusting the external fixation strut 100, 1100, 4100 may also include
moving the acute adjustment mechanism 200, 1200, 4200 relative to the threaded rod
120 to a position closer to a final adjustment position while the acute adjustment
mechanism 200, 1200, 4200 is disengaged from the threaded rod 120. The movement may
be accomplished manually or by a force created by a motorized drive, pneumatics, hydraulics,
or other effective force. The acute adjustment mechanism 200, 1200, 4200 of the external
fixation strut 100, 1100, 4100 may then be engaged to the threads of the threaded
rod 120 by removing force against the bias toward an engaged state. For example, removing
user force may include removing force from the disengagement member 230, 1230, 4230
as biased by their respective springs to the state illustrated in FIGS. 9B, 13D, and
20E.
[0099] An example, outside the scope of the claims, is a method of adjusting an external
fixation strut, such as the external fixation strut 3100. Such a method may include
disengaging an acute adjustment mechanism 3200 of the external fixation strut 3100
from threads of a threaded rod 120 of the external fixation strut 3100. The acute
adjustment mechanism 3200 may be biased toward a disengaged state. The threaded rod
120 shown is substantially rotationally fixed relative to a strut body 1110 of the
external fixation strut 3100 so that movement of the threaded rod 120 axially translates
or moves the threaded rod 120 relative to the strut body 1110. In some embodiment,
the threaded rod 120 may be substantially rotationally fixed relative to a strut body
1110 of the external fixation strut 3100 by, for example, the tracer pin 610 shown
in FIG. 10. In the illustrated embodiment, disengaging the acute adjustment mechanism
3200 of the external fixation strut 3100 from threads of a threaded rod 120 includes
allowing the two substantially oppositely positioned mobile jaws 3220 to separate.
This may include allowing the disengagement member 3230 to translate away from the
threaded rod 120. Specifically, as shown in FIG. 18C, the disengagement member 3230
is allowed to translate away from the threaded rod 120 by removing the band 3400 from
the device.
[0100] In this state, the acute adjustment mechanism 3200 may be moved relative to the threaded
rod to a position closer to a final adjustment position. The movement may be accomplished
manually or by a force created by a motorized drive, pneumatics, hydraulics, or other
effective force. The acute adjustment mechanism 3200 of the external fixation strut
1100 may then be engaged to the threads of the threaded rod 120 by applying force
against the bias toward a disengaged state. For example, user force may be applied
against the disengagement member 3230.
[0101] In the embodiment illustrated in FIGS. 17-18D, engaging the acute adjustment mechanism
3200 of the external fixation strut 3100 to the threads of the threaded rod 120 includes
applying force to the disengagement member 3230 against the bias toward a disengaged
state. The band 3400 may be placed over the actuator body 3210 of the acute adjustment
mechanism 3200 to keep the acute adjustment mechanism engaged with the threads of
the threaded rod 120.
[0102] Methods of adjusting the external fixation strut 100, 1100, 3100, 4100 may also include
releasing a lock of a precise adjustment mechanism 300, 1300 that is configured to
lock between the strut body 110, 1110 and the acute adjustment mechanism 200, 1200,
3200, 4200. For example, in the embodiment shown in FIGS. 1A-9D, the lock includes
the plunger 320 coupled to the strut body 110 through the body 310 of the precise
adjustment mechanism, and the plunger 320 is releasable from the cavities 252 in the
threaded collar 250 that is part of the acute adjustment mechanism 200 by translating
the plunger 320 away from its locked state in the cavity 252. Movement of the plunger
320 illustrated away from its locked state includes overcoming the spring bias of
the spring 330.
[0103] In the embodiments shown in FIGS. 11A-16, FIGS. 17-18D, and FIGS. 19-21B, the lock
includes the notches 1180 that are part of the strut body 1110, and the body 1310
of the precise adjustment mechanism 1300 coupled to the acute adjustment mechanism
1200, 3200, 4200 is releasable from the notches 1180 by pivoting the body 1310 of
the precise adjustment mechanism 1300 away from its locked state in the notch 1180.
Movement of the body 1310 of the precise adjustment mechanism 1300 away from its locked
state includes overcoming the spring bias of the spring 1330.
[0104] With the lock of the precise adjustment mechanism 300, 1300 in a released state,
another act of the method of adjusting the external fixation strut 100, 1100, 3100,
4100 includes rotating the acute adjustment mechanism 200, 1200, 3200, 4200 relative
to the strut body 110, 1110 to move the threaded rod 120 longitudinally relative to
the strut body 110, 1110. A result of such rotation is a lengthening or shortening
of the external fixation strut 100, 1100, 3100, 4100 as may be prescribed to achieve
external fixation goals.
[0105] In some implementations, one end of the external fixation strut 100, 1100, 3100,
4100 may be coupled to an upper base, and an opposite send of the external fixation
strut 100, 1100, 3100, 4100 may be coupled to a lower base. In such a configuration,
the act of rotating the acute adjustment mechanism 200, 1200, 3200, 4200 relative
to the strut body 110, 1110, as detailed above, moves the upper base relative to the
lower base. In some embodiments, implementation may include coupling one end of each
of six external fixation struts 100, 1100, 3100, 4100 to an upper base and an opposite
end of each of the six external fixation struts 100, 1100, 3100, 4100 to a lower base.
In such embodiments, rotating the acute adjustment mechanism 200, 1200, 3200, 4200
of each of the six external fixation struts 100, 1100, 3100, 4100 relative to its
respective strut body 110, 1110 moves the upper base relative to the lower base.
[0106] Various embodiments of a system wholly or its components individually may be made
from any biocompatible material. Instruments that will not be implanted and remain
in a patient may not necessarily be biocompatible. For example and without limitation,
materials may include in whole or in part: non-reinforced polymers, reinforced polymers,
metals, ceramics, adhesives, reinforced adhesives, and combinations of these materials.
Reinforcing of polymers may be accomplished with carbon, metal, or glass or any other
effective material. Examples of biocompatible polymer materials include polyamide
base resins, polyethylene, Ultra High Molecular Weight (UHMW) polyethylene, low density
polyethylene, polymethylmethacrylate (PMMA), polyetheretherketone (PEEK), polyetherketoneketone
(PEKK), a polymeric hydroxyethylmethacrylate (PHEMA), and polyurethane, any of which
may be reinforced. Example biocompatible metals include stainless steel and other
steel alloys, cobalt chrome alloys, zirconium, oxidized zirconium, tantalum, titanium,
titanium alloys, titanium-nickel alloys such as Nitinol, and other superelastic or
shape-memory metal alloys.
[0107] In one example of an embodiment, an external fixation strut is disclosed, the external
fixation strut comprising: a strut body; a threaded rod substantially rotationally
fixed relative to the strut body; an acute adjustment mechanism selectively disengageable
from threads of the threaded rod, the acute adjustment mechanism comprising: an actuator
body, a mobile jaw that is engageable with threads of the threaded rod, and a disengagement
member configured to interact with the mobile jaw to disengage the mobile jaw from
the threads of the threaded rod.
[0108] In another example of an embodiment, an external fixation system is disclosed. The
external fixation system comprising: an upper base; a lower base; and at least two
struts coupled between the upper base and the lower base, at least one of the struts
comprising: a strut body; a threaded rod substantially rotationally fixed relative
to the strut body; an acute adjustment mechanism selectively disengageable from threads
of the threaded rod, the acute adjustment mechanism comprising: an actuator body,
a mobile jaw that is engageable with threads of the threaded rod, and a disengagement
member configured to interact with the mobile jaw to disengage the mobile jaw from
the threads of the threaded rod.
[0109] In these and other embodiments, the external fixation strut may further comprise
a precise adjustment mechanism comprising a lock between the strut body and the actuator
body; wherein the lock is biased to fix the strut body with the actuator body rotationally,
but may be activated to allow for rotation of the actuator body relative to the strut
body to move the threaded rod longitudinally relative to the strut body.
[0110] In these and other embodiments, the lock of the precise adjustment mechanism includes
a base coupled to the strut body, a plunger biased away from the base, and a cavity
in the actuator body sized to receive the plunger to restrict rotational movement
of the strut body relative to the actuator body.
[0111] In these and other embodiments, the lock of the precise adjustment mechanism includes
a pivot coupled to the actuator body with a portion biased toward the strut body configured
to fit in a notch in the strut body to restrict rotational movement of the strut body
relative to the actuator body when the portion is in the notch in the strut body.
[0112] In these and other embodiments, the mobile jaw may include a threaded surface configured
to engage with threads of the threaded rod.
[0113] In these and other embodiments, the acute adjustment mechanism may include two substantially
oppositely positioned mobile jaws configured to engage with threads of the threaded
rod on substantially opposite sides of the threaded rod.
[0114] In these and other embodiments, the substantially oppositely positioned mobile jaws
each include a threaded surface configured to engage with threads of the threaded
rod.
[0115] In these and other embodiments, the mobile jaw is biased to engage with the threaded
rod.
[0116] In these and other embodiments, the mobile jaw is biased to disengage from the threaded
rod.
[0117] In these and other embodiments, the disengagement member is a button configured to
interact with the mobile jaw to disengage the mobile jaw from the threads of the threaded
rod when the button is moved by a user.
[0118] In these and other embodiments, the button includes an angled face configured to
interact with one or more faces of the mobile jaw to disengage the mobile jaw from
the teeth of the threaded rod.
[0119] In these and other embodiments, the button includes a rounded face configured to
interact with one or more faces of the mobile jaw to disengage the mobile jaw away
from the threaded rod.
[0120] In these and other embodiments, the disengagement member is configured to translate
toward the mobile jaw to disengage the mobile jaw from the threaded rod and to be
rotated about the disengagement member's axis of translation to lock the acute adjustment
mechanism in a state of free movement where the mobile jaw is disengaged from the
threaded rod.
[0121] In these and other embodiments, the disengagement member is configured to translate
away from the mobile jaw to enable the mobile jaw to disengage from the threaded rod.
[0122] In these and other embodiments, the disengagement member includes a containment device
configured to prevent the mobile jaw from moving away from the threads of the threaded
rod when the containment device is coupled to the acute adjustment mechanism.
[0123] In these and other embodiments, the containment device is arranged and configured
as an ID band.
[0124] In these and other embodiments, the mobile jaw is configured to translate away from
the threaded rod when interacted with by the disengagement member.
[0125] In these and other embodiments, the mobile jaw is configured to pivot away from the
threaded rod when interacted with by the disengagement member.
[0126] In these and other embodiments, the actuator body includes a threaded collar that
couples the actuator body with the strut body.
[0127] In these and other embodiments, the actuator body includes channels configured to
guide the movement of the mobile jaw when the mobile jaw is interacted with the disengagement
member.
[0128] In these and other embodiments, the actuator body includes channels configured to
constrain the movement of protrusions on the mobile jaw when the mobile jaw is interacted
on by the disengagement member.
[0129] In these and other embodiments, the mobile jaw has one or more angled faces configured
to interact with the disengagement member to move the mobile jaw away from the threaded
rod.
[0130] In these and other embodiments, the external fixation strut may also include a rotatable
sleeve that is sized to fit over the outside of the actuator body with one or more
openings for access to the disengagement member.
[0131] In these and other embodiments, when the rotatable sleeve is rotated relative to
the actuator body, access to the disengagement member is blocked.
[0132] In these and other embodiments, when the rotatable sleeve is rotated relative to
the actuator body a portion of opening interacts with the disengagement member to
disengage the mobile jaw from the threaded rod.
[0133] In these and other embodiments, the actuator body includes openings for projections
of a band to prevent disengagement of the mobile jaw from the threaded rod.
[0134] In these and other embodiments, a band covers the disengagement member when the band
is positioned on the acute adjustment mechanism to prevent access to the disengagement
member.
[0135] In these and other embodiments, the external fixation strut may also include connectors
for coupling with one or both of the upper base and the lower base.
[0136] In these and other embodiments, the external fixation struct may also include bone
fixation mechanisms for coupling between the connectors and tissue of a patient.
[0137] In another example, outside the scope of the claims, a method of adjusting an external
fixation strut is disclosed. The method comprising: disengaging an acute adjustment
mechanism of the external fixation strut from threads of a threaded rod of the external
fixation strut, wherein the acute adjustment mechanism is biased toward an engaged
state, and wherein the threaded rod is substantially rotationally fixed relative to
a strut body of the external fixation strut; moving the acute adjustment mechanism
relative to the threaded rod to a position closer to a final adjustment position;
and engaging the acute adjustment mechanism of the external fixation strut to the
threads of the threaded rod by removing force against the bias toward an engaged state.
[0138] In another example, outside the scope of the claims, a method of adjusting an external
fixation strut is disclosed. The method comprising: disengaging an acute adjustment
mechanism of the external fixation strut from threads of a threaded rod of the external
fixation strut, wherein the acute adjustment mechanism is biased toward a disengaged
state, and wherein the threaded rod is substantially rotationally fixed relative to
a strut body of the external fixation strut; moving the acute adjustment mechanism
relative to the threaded rod to a position closer to a final adjustment position;
and engaging the acute adjustment mechanism of the external fixation strut to the
threads of the threaded rod by applying force against the bias toward a disengaged
state.
[0139] In these and other examples, the method may further comprise releasing a lock of
a precise adjustment mechanism that is configured to lock between the strut body and
the acute adjustment mechanism; wherein with the lock of the precise adjustment mechanism
in a released state, rotating the acute adjustment mechanism relative to the strut
body to move the threaded rod longitudinally relative to the strut body.
[0140] In these and other examples, releasing the lock of the precise adjustment mechanism
includes overcoming a spring bias of the lock toward a locked state.
[0141] In these and other examples, releasing the lock of the precise adjustment mechanism
includes translating a lock component away from a locked state.
[0142] In these and other examples, releasing the lock of the precise adjustment mechanism
includes rotating a lock component away from a locked state.
[0143] In these and other embodiments, disengaging an acute adjustment mechanism of the
external fixation strut from threads of the threaded rod of the external fixation
strut includes separating two substantially oppositely positioned mobile jaws.
[0144] In these and other embodiments, separating the two substantially oppositely positioned
mobile jaws includes moving a disengagement member into contact with both of the mobile
jaws.
[0145] In these and other embodiments, separating the two substantially oppositely positioned
mobile jaws includes translating the two substantially oppositely positioned mobile
jaws away from the threaded rod.
[0146] In these and other embodiments, separating the two substantially oppositely positioned
mobile jaws includes pivoting the two substantially oppositely positioned mobile jaws
away from the threaded rod.
[0147] In these and other embodiments, disengaging an acute adjustment mechanism of the
external fixation strut from threads of the threaded rod of the external fixation
strut includes allowing two substantially oppositely positioned mobile jaws to separate.
[0148] In these and other embodiments, allowing the two substantially oppositely positioned
mobile jaws to separate includes allowing a disengagement member to translate away
from the threaded rod.
[0149] In these and other embodiments, allowing the two substantially oppositely positioned
mobile jaws to separate includes removing a band from the disengagement member.
[0150] In these and other examples, the method may further comprise coupling one end of
the external fixation strut to an upper base and an opposite end of the external fixation
strut to a lower base, and wherein rotating the acute adjustment mechanism relative
to the strut body moves the upper base relative to the lower base.
[0151] In these and other examples, the method may further comprise coupling one end of
each of six external fixation struts to an upper base and an opposite end of each
of the six external fixation struts to a lower base, and wherein rotating the acute
adjustment mechanism of each of the six external fixation struts relative to its respective
strut body moves the upper base relative to the lower base.
[0152] Terms such as closer, underneath, over, around, medial, lateral, inside, outside
and the like have been used relatively herein. However, such terms are not limited
to specific coordinate orientations, distances, or sizes, but are used to describe
relative positions referencing particular embodiments. Such terms are not generally
limiting to the scope of the claims made herein. Any embodiment or feature of any
section, portion, or any other component shown or particularly described in relation
to various embodiments of similar sections, portions, or components herein may be
interchangeably applied to any other similar embodiment or feature shown or described
herein.
[0153] The foregoing description has broad application. While embodiments of the invention
have been illustrated and described in detail in the disclosure, the disclosure is
to be considered as illustrative and not restrictive in character. All changes and
modifications that come within the scope of the claims are to be considered within
the scope of the disclosure. Accordingly, the discussion of any embodiment is meant
only to be explanatory and is not intended to suggest that the scope of the disclosure,
including the claims, is limited to these examples. In other words, the scope of the
invention is defined by the appended claims.
[0154] The foregoing discussion has been presented for purposes of illustration and description
and is not intended to limit the disclosure to the form or forms disclosed herein.
For example, various features of the disclosure are grouped together in one or more
aspects, embodiments, or configurations for the purpose of streamlining the disclosure.
However, it should be understood that various features of the certain aspects, embodiments,
or configurations of the disclosure may be combined in alternate aspects, embodiments,
or configurations.
[0155] The phrases "at least one", "one or more", and "and/or", as used herein, are open-ended
expressions that are both conjunctive and disjunctive in operation. For example, each
of the expressions "at least one of A, B and C", "at least one of A, B, or C", "one
or more of A, B, and C", "one or more of A, B, or C" and "A, B, and/or C" means A
alone, B alone, C alone, A and B together, A and C together, B and C together, or
A, B and C together.
[0156] The term "a" or "an" entity, as used herein, refers to one or more of that entity.
As such, the terms "a" (or "an"), "one or more" and "at least one" can be used interchangeably
herein. The use of "including," "comprising," or "having" and variations thereof herein
is meant to encompass the items listed thereafter as well as additional items. Accordingly,
the terms "including," "comprising," or "having" and variations thereof are open-ended
expressions and can be used interchangeably herein.
[0157] All directional references (e.g., proximal, distal, upper, lower, upward, downward,
left, right, lateral, longitudinal, front, back, top, bottom, above, below, vertical,
horizontal, radial, axial, clockwise, and counterclockwise) are only used for identification
purposes to aid the reader's understanding of the present disclosure, and do not create
limitations, particularly as to the position, orientation, or use of this disclosure.
Connection references (e.g., attached, coupled, connected, and joined) are to be construed
broadly and may include intermediate members between a collection of elements and
relative movement between elements unless otherwise indicated. As such, connection
references do not necessarily infer that two elements are directly connected and in
fixed relation to each other. Identification references (e.g., primary, secondary,
first, second, third, fourth, etc.) are not intended to connote importance or priority
but are used to distinguish one feature from another. The drawings are for purposes
of illustration only and the dimensions, positions, order and relative sizes reflected
in the drawings attached hereto may vary.